[img]/phpBB/images/smiles/icon_cool.gif[/img]it can because you are washing fuel down into the pan, which removes the oil film from the cylinder walls and leads to extra wear.
[addsig]
Fuel/oil dissolution will ruin bearing, ring seal, lesser the oil weight and can actually be explosive if it gets bad enough.[img]/phpBB/images/smiles/icon_frown.gif[/img]